The tasks of video deinterlacing and film-mode detection challenge conventional deinterlacers to achieve a best quality for a minimal memory bandwidth cost. Part of the challenge is a lack of flexibility to trade off memory bandwidth and quality in the conventional deinterlacers. High quality state-of-the-art video deinterlacers use multiple fields of video buffered in a memory to create progressive frames for display. Additionally, high quality state-of-the-art film mode detection units (that are typically used with deinterlacers) use multiple fields from the memory.
Some existing deinterlacers and conventional film mode detectors are designed to use subsampled or decimated fields to save memory storage and bandwidth. However, quality suffers when the subsampled/decimated fields are used for generating the progressive frames. Other existing devices use fewer fields or more fields of video, with or without various color or chrominance components, as inputs to the deinterlacer modules and the film mode detection modules. The varying numbers of fields are used to trade off quality for memory bandwidth.
The existing solutions do not permit configurable and/or flexible use of downsampling/decimation. In particular, the resolution of the various fields consumed, as stored in an external memory, is consistent in existing solutions. For example, existing devices do not simultaneously store different resolution versions of the same field in the external memory. Furthermore, the existing solutions are not configurable such that a first specified field resolution may be used for stationary pixel checking and/or film mode detection, while a second specified field resolution may be used for pixel generation by the deinterlacing unit. The existing solutions do not write the reduced resolution versions of the fields back to the external memory to be used later for the processing of subsequent fields. Still further, the existing solutions are not configurable in the amount and type of decimation that is used depending on the type of film mode detected.